Antrioventricaular Blocks in Acute Inferior Myocardial Infarction

ABSTRACT

To evaluate the clinical significance of atrioventricular blocks in acute inferior myocardial infarction, we reviewed the clinical recordes of 75 patients who were diagnosed as acute inferior myocardial infarction with or without associated atrioventricular conduction blocks and compared the difference in clinical observation and laboratory data including coronary angiography between these two groups of patients. We also followed the clinical courses of atrioventrticualr block during admission among the patients with blocks. 1) 40% of 75 patients had atrioventricualr block associated with acute inferior myocardial infarction and there were 7 first-degree, 8 second-degree and 15 third-degree atrioventricular blocks. 2) There was no statistically significant differences between two groups in mean age ; Killip classification incidence of previous prodromal angina ; incidende of associated initial symptoms such as dyspnea, nausea, and syncope ; risk factors such as smoking, hypertension and previous muocardial infarction and incidence of complication such as ventricular arrhythmias and heart faliure. 3) The peak serum CK(1,442.9+/-1,703.6 vs. 1,942.8+/-2,022.9IU/L, P<0.01)and LDH(1,014.7+/-429.7 vs. 1,579.2+/-1,544.9 IU/L, P<0.01) levels were significantly higher in the patients group with atrioventricualr blocks than in the patient grouop without blocks. 4) Left ventricualr resting ejection fraction obtained by radinuclide geted blood pool heart scan was significantly less in the patient group with atrioventricular blocks than in the patient group without blocks. 5) The prevalence of multivessel disease and that of associated left anterior descending artery lesion showe no differences between two patient groups. 6) Hospatal mortality of two patient groups were 9.8% and 16.6% respectively and had no statistical significance. 7) Among the patients who had associated atrioventricualr blocks, 70% of patients showed temporary course of block for mean 4.8days, and 6.7% developed permanent first degree block.